Philip Kapleau (1912–2004) was a teacher of Zen Buddhism in the Sanbo Kyodan tradition, a blending of Japanese Sōtō and Rinzai schools.
Kapleau was born in New Haven, Connecticut. As a teenager, he worked as a bookkeeper. He briefly studied law and later became an accomplished court reporter. In 1945 he served as chief Allied court reporter for the "Trial of the Major War Criminals Before the International Military Tribunal", which judged the leaders of Nazi Germany. This was the first of the series commonly known as the Nuremberg Trials.
Kapleau later covered the International Military Tribunal for the Far East, commonly known as the Tokyo War Crimes Trials. While in Japan he became intrigued by and drawn to Zen Buddhism. During the tribunal he became acquainted with Karlfried Graf Dürckheim, then a prisoner at Sugamo Prison, who recommended that Kapleau attend informal lectures given by D.T. Suzuki in Kita-Kamakura. After returning to America, Kapleau renewed his acquaintance with D.T. Suzuki who had left Kita-Kamakura to lecture on Zen at Columbia University. But disaffected with a primarily intellectual treatment of Zen, he moved to Japan in 1953 to seek Zen's deeper truth.
He trained initially with Soen Nakagawa, then rigorously with Daiun Harada at the temple Hosshin-ji. Later he became a disciple of Hakuun Yasutani, himself a dharma heir of Harada. After 13 years' training, Kapleau was ordained by Yasutani in 1965 and given permission to teach. Kapleau ended his relationship with Yasutani formally in 1967 over disagreements about teaching and other personal issues. According to Ford, "Kapleau had completed about half of the Harada-Yasutani kōan curriculum, the koans in the Gateless Gate and the Blue Cliff Record," and was entitled to teach, but did not receive dharma transmission. According to Andrew Rawlinson, "Kapleau has created his own Zen lineage."